1. Field
Example embodiments of the inventive concepts relate to a semiconductor memory device, and more particularly, to a resistive memory device including a resistive element.
2. Description of Related Art
With development of a mobile system and various application systems, there has been an increasing need for non-volatile memories. The examples of next generation memory devices becoming increasingly popular include a phase change random access memory (PRAM) using a phase change material, a resistive random access memory (RRAM) using a variable resistance material, such as transition metal oxides, and a magnetic random access memory (MRAM) using a ferromagnetic material. These next generation memory devices have in common the fact that their resistances vary depending on an electric current or voltage, and even when the current or voltage is cut off, the resistance values are maintained so that refreshing the memory is not required because of their non-volatility.
The above described MRAM includes a magnetic upper electrode, a magnetic lower electrode, and a magnetic tunnel junction (MTJ) including a dielectric material between the upper and lower electrodes. Reading data from the MRAM can be achieved by determining a resistance state inside a certain cell caused by a tunneling magnetroresistance of the MTJ. Accordingly, in view of such a data read operation principle of the MRAM, which is based on the difference in resistance, resistance distribution management of the MRAM may be very important when improving the operation characteristics thereof.